Single frame cannot be encoded with -vcodec hevc

[Carl Eugen Hoyos]

At least 20 frames have to be encoded with libx265 to get a useful output file.

$ ffmpeg -loop 1 -i tests/lena.pnm -threads 1 -vcodec hevc -pix_fmt yuv420p -vframes 19 out.mov
ffmpeg version N-63932-g681868c Copyright (c) 2000-2014 the FFmpeg developers
  built on Jun 13 2014 16:26:27 with Apple LLVM version 5.1 (clang-503.0.40) (based on LLVM 3.4svn)
  configuration: --enable-libx265 --enable-gpl
  libavutil      52. 89.100 / 52. 89.100
  libavcodec     55. 66.100 / 55. 66.100
  libavformat    55. 43.100 / 55. 43.100
  libavdevice    55. 13.101 / 55. 13.101
  libavfilter     4.  8.100 /  4.  8.100
  libswscale      2.  6.100 /  2.  6.100
  libswresample   0. 19.100 /  0. 19.100
  libpostproc    52.  3.100 / 52.  3.100
Input #0, image2, from 'tests/lena.pnm':
  Duration: 00:00:00.04, start: 0.000000, bitrate: N/A
    Stream #0:0: Video: ppm, rgb24, 256x256, 25 fps, 25 tbr, 25 tbn, 25 tbc
x265 [info]: HEVC encoder version 1.1+88-e69a427e461f
x265 [info]: build info [Mac OS X][clang 5.1.0][64 bit] 8bpp
x265 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.1 Cache64
x265 [info]: WPP streams / pool / frames         : 4 / 2 / 1
x265 [info]: Main profile, Level-2 (Main tier)
x265 [info]: CU size                             : 64
x265 [info]: Max RQT depth inter / intra         : 1 / 1
x265 [info]: ME / range / subpel / merge         : hex / 57 / 2 / 2
x265 [info]: Keyframe min / max / scenecut       : 25 / 250 / 40
x265 [info]: Lookahead / bframes / badapt        : 20 / 4 / 2
x265 [info]: b-pyramid / weightp / weightb / refs: 1 / 1 / 0 / 3
x265 [info]: Rate Control / AQ-Strength / CUTree : ABR-200 kbps / 1.0 / 1
x265 [info]: tools: rd=3 lft sao-lcu signhide 
Output #0, mov, to 'out.mov':
  Metadata:
    encoder         : Lavf55.43.100
    Stream #0:0: Video: hevc (libx265) (hev1 / 0x31766568), yuv420p, 256x256, q=2-31, 200 kb/s, 25 fps, 12800 tbn, 25 tbc
    Metadata:
      encoder         : Lavc55.66.100 libx265
Stream mapping:
  Stream #0:0 -> #0:0 (ppm (native) -> hevc (libx265))
Press [q] to stop, [?] for help
frame=   19 fps=0.0 q=0.0 Lsize=       0kB time=00:00:00.00 bitrate=N/A    
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
x265 [info]: consecutive B-frames: 100.0% 0.0% 0.0% 0.0% 0.0%

$ ffmpeg -i out.mov 
ffmpeg version N-63932-g681868c Copyright (c) 2000-2014 the FFmpeg developers
  built on Jun 13 2014 16:26:27 with Apple LLVM version 5.1 (clang-503.0.40) (based on LLVM 3.4svn)
  configuration: --enable-libx265 --enable-gpl
  libavutil      52. 89.100 / 52. 89.100
  libavcodec     55. 66.100 / 55. 66.100
  libavformat    55. 43.100 / 55. 43.100
  libavdevice    55. 13.101 / 55. 13.101
  libavfilter     4.  8.100 /  4.  8.100
  libswscale      2.  6.100 /  2.  6.100
  libswresample   0. 19.100 /  0. 19.100
  libpostproc    52.  3.100 / 52.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'out.mov':
  Metadata:
    major_brand     : qt  
    minor_version   : 512
    compatible_brands: qt  
    encoder         : Lavf55.43.100
  Duration: 00:00:00.00, bitrate: N/A
At least one output file must be specified

[Michael Niedermayer]

does it work with the x265 command line tool instead of ffmpeg ?

[Carl Eugen Hoyos]

The following produces an empty file:

$ ./ffmpeg -i tests/lena.pnm -pix_fmt yuv420p out.y4m
$ ./ffmpeg -i out.y4m out.hevc

The following works fine:

$ x265 out.y4m out.hevc